Molecular weight control of polyolefins using halogenated bis-phenylphenoxy catalysts

ABSTRACT

A process for preparing an olefin homopolymer or copolymer comprises contacting ethylene, an alpha-olefin, or a combination, and a catalytic amount of a metal-ligand complex catalyst of a particular formula that requires at least one halogen atom that is ortho to a bridging moiety. The strategic location of the halogen atom(s) ensures a product having a molecular weight that is predictably and significantly reduced in comparison with that of copolymers produced using otherwise identical metal-ligand complex catalysts that lack halogen atoms at the specified sites.

REFERENCE TO RELATED APPLICATIONS

This application is filed as a continuation of U.S. Pat. No. 9,605,098,filed on Sep. 30, 2015; which is a national stage entry ofPCT/US2014/044374, filed Jun. 26, 2014; which claims priority to U.S.Provisional Application No. 61/840,624, filed on Jun. 28, 2013, thedisclosures of which are incorporated herein by reference.

The invention relates to molecular weight control of polyolefins. Moreparticularly, it relates to preparation of ethylene or alpha-olefinhomopolymers or ethylene/alpha-olefin copolymers using a particularfamily of bis-phenylphenoxy catalysts that predictably alter polymermolecular weight.

Polyolefins that are polyethylene polymers, poly(ethylene alpha-olefin)copolymers, and mixtures or blends of such polyolefins are examples oftypes of polyolefins widely used in industry. They are desirable formaking, for example, containers, tubing, films and sheets for packaging,and synthetic lubricants and other utility fluids. The polymerization ofethylene, and polymerization of ethylene and alpha-olefins, bytransition metal catalysts is generally known to produce relatively highmolecular weight polymers and copolymers. Frequently such polymers andcopolymers exhibit molecular weight ranges of greater than 100,000Daltons (Da), and in some embodiments greater than 500,000 Da. At thesemolecular weight levels, rheological behavior may be undesirable,however, because the products may not flow as desired and mayfurthermore tend to crystallize from solution.

Those skilled in the art have sought ways and means to control and/orpredict molecular weight. It is recognized that selection of startingmonomers, catalysts, and processing conditions may each affect theweight average molecular weight (Mw) of the polymers or copolymers beingprepared. Catalyst choices may also be customized for other distinct orrelated reasons, such as overall reactivity profile.

For example, U.S. Pat. No. 6,869,904 B2 and U.S. Pat. No. 7,060,848 B2mention catalysts including certain ligands, metals and arrays withsubstituted bridged bis-aromatic or bridged bis-biaromatic ligands.

PCT International Patent Application Publication Number WO 2007/136494A2 mentions a catalyst composition comprising a zirconium complex of apolyvalent aryloxy ether and the use thereof in a continuous solutionpolymerization of ethylene, one or more C₃-C₃₀ olefins, and a conjugatedor non-conjugated diene to prepare interpolymers having improvedprocessing properties. The catalyst system contains a catalystcovalently bonded to an activator.

One particular group of catalysts is described in United States PatentPublication US20110282018 as effective to polymerize alpha-olefins andethylene/alpha-olefins. These metal ligand complex catalysts aredescribed as bis-phenylphoxy compounds that may or may not containhalogens in formula-determined locations which are, in some potentialembodiments, ortho to a bridging moiety.

There remains a need in the art for convenient, efficient andcontrollable processes to tailor the rheological behavior of an olefinicproduct to a greater variety of specific end use applications.

In a first embodiment, the present invention is a process for preparingan olefin homopolymer or copolymer, comprising contacting ethylene, analpha-olefin, or a combination thereof, and a catalytic amount of ametal-ligand complex catalyst of the formula

wherein M is titanium, zirconium, or hafnium, each independently beingin a formal oxidation state of +2, +3, or +4; n is an integer of from 0to 3, wherein when n is 0, X is absent; each X is independently amonodentate ligand that is neutral, monoanionic, or dianionic, or two Xare taken together to form a bidentate ligand that is neutral,monoanionic, or dianionic; X and n are selected such that themetal-ligand complex is neutral; each Z moiety independently is O, S,N(C₁-C₄₀) hydrocarbyl, or P(C₁-C₄₀) hydrocarbyl; L is(C₁-C₄₀)hydrocarbylene or (C₁-C₄₀)heterohydrocarbylene, provided suchhas a portion that comprises a 2- to 8-carbon atom linker backbonelinking the Z moieties, each atom of such 2- to 8-atom linker beingindependently a carbon atom or a heteroatom, wherein each heteroatomindependently is O, S, S(O), S(O)₂, Si(R^(C))₂, Ge(R^(C))₂, P(R^(P)), orN(R^(N)); R^(1a), R^(1b), or both is a halogen atom; and R^(2a), R^(3a),R^(4a), R^(2b), R^(3b), R^(4b), R^(6c), R^(7c), R^(8c), R^(6d), R^(7d),and R^(8d) independently is a hydrogen atom; (C₁-C₄₀)hydrocarbyl;(C₁-C₄₀)heterohydrocarbyl; Si(R^(C))₃, Ge(R^(C))₃, P(R^(P))₂, N(R^(N))₂,OR^(C), SR^(C), NO₂, CN, F₃C, F₃CO, RCS(O)—, RCS(O)₂—, (RC)₂C═N—,RCC(O)O—, RCOC(O)—, RCC(O)N(R)—, (RC)2NC(O)— or halogen atom; each ofR^(5c) and R^(5d) is independently a (C₆-C₄₀)aryl or (C₁-C₄₀)heteroaryl;and each of the aryl, heteroaryl, hydrocarbyl, heterohydrocarbyl,hydrocarbylene, and heterohydrocarbylene groups is independentlyunsubstituted or substituted with one or more substituents R^(S); andeach R^(S) is independently a halogen atom, polyfluoro substitution,perfluoro substitution, unsubstituted (C₁-C₁₈)alkyl, F₃C—, FCH₂O—,F₂HCO—, F₃CO—, R₃Si—, R₃Ge—, RO—, RS—, RS(O)—, RS(O)₂—, R₂P—, R₂N—,R₂C═N—, NC—, RC(O)O—, ROC(O)—, RC(O)N(R)—, or R₂NC(O)—, or two of theR^(S) are taken together to form an unsubstituted (C₁-C₁₈)alkylene,wherein each R independently is an unsubstituted (C₁-C₁₈)alkyl; underconditions such that an ethylene homopolymer, an alpha-olefinhomopolymer, or an ethylene/alpha-olefin copolymer is formed, suchhaving a weight average molecular weight that is reduced by at least 20percent when compared with an otherwise identical ethylene homopolymer,alpha-olefin homopolymer or ethylene/alpha-olefin copolymer preparedunder identical conditions with a catalyst that is otherwise identicalbut wherein neither R^(1a) nor R^(1b) is a halogen atom.

The inventive process surprisingly offers the advantage of greatlyreducing molecular weight of a given ethylene or alpha-olefinhomopolymer or ethylene/alpha-olefin copolymer without otherwisesignificantly modifying the nature of the homopolymerization orcopolymerization. This molecular weight reduction, in turn, may offer asignificant increase in flow behavior that correspondingly may increasethe number and types of applications for use of these products.

The advantage is obtained by use as catalysts of a particular subset ofthe bis-phenylphenoxy compounds described in US20110282018. These aretermed metal-ligand complex catalysts that combine a transition metalcenter and any of a wide variety of bis-phenylphenoxy-containing ligandsconforming to formula (I), provided that the following limitations aremet. First, the bridge, L, between the Z moieties is from 2 atoms to 8atoms in length. Second, the Z moieties may be selected independentlyfrom oxygen, sulfur, phosphorus(C₁₋₄₀)hydrocarbyl, andnitrogen(C₁₋₄₀)hydrocarbyl. Third, the ligand has a halogen atom locatedin at least one of the positions on the benzene rings in the R^(1a)and/or R^(1b) position of formula (I), i.e., at a position, orpositions, that is/are ortho to the bridged Z moieties. The term“halogen atom” means a fluorine atom radical (F), chlorine atom radical(Cl), bromine atom radical (Br), or iodine atom radical (I). Preferablyeach halogen atom independently is a Br, F, or Cl radical, and morepreferably a F or Cl radical. Fourth, the metal M is preferably selectedfrom zirconium (Zr), hafnium (Hf), and titanium (Ti), and morepreferably is either Zr or Hf.

The members of the catalyst family defined as being useful for reductionof homopolymer or copolymer weight average molecular weight (M_(w)) aregenerally convenient to prepare and may operate efficiently and over awide thermal operating range, in some non-limiting embodimentswithstanding temperatures exceeding 200° C. Such catalysts may,themselves, be of effectively any M_(w), but in certain non-limitingembodiments preferably range from 200 Daltons (Da) to 5,000 Da.Preparation may include, in non-limiting embodiments, construction of asuitable ligand structure followed by its reaction with a salt of thedesired transition metal, which effects the desired metal-ligandcomplexation. Additional and highly detailed preparation information maybe found in the examples included herein below, as well as in, e.g., thepreviously referenced US20110282018; US Serial NumberPCT/US2012/0667700, filed Nov. 28, 2012, claiming priority to U.S.Provisional Application 61/581,418, filed Dec. 29, 2011; and U.S. Ser.No. 13/105,018, filed May 11, 2011, Publication Number 20110282018,claiming priority to US Provisional Application 61/487,627, filed Mar.25, 2011. Those skilled in the art will recognize that similar andanalogous processes may be used to prepare other usefulbis-phenylphenoxy compounds falling within the given general definition.

Such suitable catalysts may generally include, in more specific butnon-limiting embodiments, metal-ligand complexes of formula (I)

wherein M is titanium, zirconium, or hafnium, each independently beingin a formal oxidation state of +2, +3, or +4; n is an integer of from 0to 3, wherein when n is 0, X is absent; each X independently is amonodentate ligand that is neutral, monoanionic, or dianionic, or two Xare taken together to form a bidentate ligand that is neutral,monoanionic, or dianionic; X and n are selected such that themetal-ligand complex is, overall, neutral; each Z is independently O, S,N(C₁-C₄₀)hydrocarbyl, or P(C₁-C₄₀)hydrocarbyl; L is(C₁-C₄₀)hydrocarbylene or (C₁-C₄₀)-heterohydrocarbylene, wherein the(C₁-C₄₀)hydrocarbylene has a portion that comprises a 2- to 8-atomlinker backbone linking the Z moieties and the(C₁-C₄₀)heterohydrocarbylene has a portion that comprises a 2- to 8-atomlinker backbone linking the Z moieties, wherein each atom of the 2- to8-atom linker of the (C₁-C₄₀)heterohydrocarbylene independently is acarbon atom or a heteroatom, wherein each heteroatom independently is O,S, S(O), S(O)₂, Si(R^(C))₂, Ge(R^(C))₂, P(R^(P)), or N(R^(N)), whereinindependently each R^(C) is unsubstituted (C₁-C₁₈)hydrocarbyl or the twoR^(C) are taken together to form a (C₂-C₁₉)alkylene, each R^(P) isunsubstituted (C₁-C₁₈)hydrocarbyl; and each R^(N) is unsubstituted(C₁-C₁₈)hydrocarbyl, a hydrogen atom or absent; R^(1a), R^(1b), or bothis a halogen atom; and R^(2a), R^(3a), R^(4a), R^(2b), R^(3b), R^(4b),R^(6c), R^(7c), R^(8c), R^(6d), R^(7d), and R^(8d) independently is ahydrogen atom; (C₁-C₄₀)hydrocarbyl; (C₁-C₄₀)heterohydrocarbyl;Si(R^(C))₃, Ge(R^(C))₃, P(R^(P))₂, N(R^(N))₂, OR^(C), SR^(C), NO₂, CN,F₃C, F₃CO, RCS(O)—, RCS(O)₂—, (RC)₂C═N—, RCC(O)O—, RCOC(O)—, RCC(O)(R)—,(RC)2NC(O)— or halogen atom; each of R^(5c) and R^(5d) is independentlya (C₆-C₄₀)aryl or (C₁-C₄₀)heteroaryl; and each of the aryl, heteroaryl,hydrocarbyl, heterohydrocarbyl, hydrocarbylene, and heterohydrocarbylenegroups is independently unsubstituted or substituted with one or moresubstituents R^(S); and each R^(S) is independently a halogen atom,polyfluoro substitution, perfluoro substitution, unsubstituted(C₁-C₁₈)alkyl, F₃C—, FCH₂O—, F₂HCO—, F₃CO—, R₃Si—, R₃Ge—, RO—, RS—,RS(O)—, RS(O)₂—, R₂P—, R₂N—, R₂C═N—, NC—, RC(O)O—, ROC(O)—, RC(O)N(R)—,or R₂NC(O)—, or two of the R^(S) are taken together to form anunsubstituted (C₁-C₁₈)alkylene, wherein each R independently is anunsubstituted (C₁-C₁₈)alkyl.

A wide variety of additional substitution may be present at all othercarbons of the at least four phenyl rings included within the catalystof formula (I) or such may have simply hydrogen. Some examples ofpreferred R^(5c) and R^(5d) substituents include3,5-di(tertiary-butyl)phenyl; 3,5-diphenylphenyl; 1-naphthyl,2-methyl-1-naphthyl; 2-naphthyl; 1,2,3,4-tetrahydronaphthyl;1,2,3,4-tetrahydro-naphth-5-yl; 1,2,3,4-tetrahydronaphth-6-yl;1,2,3,4-tetrahydroanthracenyl; 1,2,3,4-tetrahydroanthracen-9-yl;1,2,3,4,5,6,7,8-octahydroanthracenyl;1,2,3,4,5,6,7,8-octahydroanthracen-9-yl; phenanthren-9-yl;1,2,3,4,5,6,7,8-octahydrophenanthren-9-yl; 2,3-dihydro-1H-inden-6-yl;naphthalene-2-yl; 1,2,3,4-tetrahydronaphthalen-6-yl;1,2,3,4-tetrahydronaphthalen-5-yl; anthracen-9-yl;1,2,3,4-tetrahydroanthracen-9-yl;1,2,3,4,5,6,7,8-octahydro-anthracen-9-yl; 2,6-dimethylphenyl;2,6-diethylphenyl; 2,6-bis(1-methylethyl)phenyl; 2,6-diphenyl-phenyl;3,5-dimethylphenyl; 3,5-bis(tri-fluoromethyl)phenyl;3,5-bis(1-methylethyl)phenyl; 3,5-bis(1,1-dimethylethyl)phenyl;3,5-diphenyl-phenyl); 2,4,6-trimethylphenyl; and2,4,6-tris(1-methylethyl)phenyl); 1-methyl-2,3-dihydro-1H-inden-6-yl;1,1-dimethyl-2,3-dihydro-1H-inden-6-yl;1-methyl-1,2,3,4-tetrahydro-naphthalen-5-yl;1,1-dimethyl-1,2,3,4-tetrahydronaph-thalen-5-yl,1,2,3,4-tetrahydroquinolinyl; isoquinolinyl;1,2,3,4-tetrahydroisoquinolinyl; carbazolyl;1,2,3,4-tetrahydrocarbazolyl; 1,2,3,4,5,6,7,8-octahydrocarbazolyl;3,6-di(tertiary-butyl)-carbazolyl; 3,6-di(tertiary-octyl)-carbazolyl;3,6-diphenylcarbazolyl; 3,6-bis(2,4,6-trimethylphenyl)-carbazolyl;3,6-di(tertiary-butyl)-carbazol-9-yl;3,6-di(tertiary-octyl)-carbazol-9-yl; 3,6-diphenylcarbazol-9-yl;3,6-bis(2,4,6-trimethylphenyl)-carbazol-9-yl; quin-olin-4-yl;quinolin-5-yl; quinolin-8-yl; 1,2,3,4-tetrahydroquinolin-1-yl;isoquinolin-1-yl; isoquinolin-4-yl; iso-quinolin-5-yl; isoquinolin-8-yl;1,2,3,4-tetrahydroisoquinolin-2-yl; 1H-indol-1-yl; 1H-indolin-1-yl;9H-carbazol-9-yl; 1,2,3,4-tetrahydrocarbazolyl-9-yl;1,2,3,4,5,6,7,8-octahydrocarbazolyl-9-yl; 4,6-bis(1,1-dimethylethyl)pyridine-2-yl; 4,6-diphenylpyridin-2-yl; 3-phenyl-1H-indol-1-yl;3-(1,1-dimethylethyl)-1H-indol-1-yl; 3,6-diphenyl-9H-carbazol-9-yl;3,6-bis[2′,4′,6′-tris(1,1-dimethylphenyl)]-9H-carbazol-9-yl;3,6-bis(1,1-dimethyl-ethyl)-9H-carba-zol-9-yl.

In certain still more specific and preferred embodiments of theinventive process, the metal-ligand complex may be selected fromcompounds represented by any of the following formulas. Additionalmoieties denoted by abbreviations include Me (methyl); t-Bu(tert-butyl); OMe (methoxy); TMS (trimethylsilyl); Et (ethyl); and iPr(isopropyl).

Once the catalyst is obtained, via purchase or preparation, it is readyfor use in the inventive process. Where alpha-olefin homopolymerizationor ethylene/alpha-olefin copolymerization is desirable, suitablealpha-olefins may be any selected according to the desired properties ofthe final copolymer. In non-limiting example only, the alpha-olefin maybe selected from linear alpha-olefins having from 3 to 12 carbons, suchas propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene,1-nonene, 1-decene, undecene, 1-dodecene, and combinations thereof.Smaller linear alpha-olefins having from 3 to 8 carbons are preferred,because they allow for a higher branch density of the final productoligomers. Branched alpha-olefins may also be employed in the processfeed, and may include in non-limiting embodiments singly and multiplybranched alpha-olefin monomers having from 5 to 16 carbons, wherein thefirst substituted carbon is at the “3” or greater position with respectto the vinyl, and combinations thereof. It is generally preferred thatthe first substitution be at the “4” or greater position.

In order to prepare the homopolymers or copolymers of the invention,ethylene and/or the selected alpha-olefin monomer(s) is/are fed into asuitable reactor, for batch, semi-continuous, or continuous production,wherein such monomer(s) will come into contact with the catalyst. In thecase of preparation of a copolymer, it is noted that theethylene/alpha-olefin reactivity ratio is distinct for any givencatalyst and provides a methodology to determine the amount ofalpha-olefin that will be required to attain a targeted copolymercomposition. Reactivity ratios may be determined using well knowntheoretical techniques or empirically derived from actual polymerizationdata. Suitable theoretical techniques are disclosed, for example, in B.G. Kyle, Chemical and Process Thermodynamics, 3^(rd) ed., Prentice-Hall(Englewood Cliffs, N.J. 1999) and in G. Soave, “Redlich-Kwong-Soave(RKS) Equation of State,” Chemical Engineering Science, 1972, vol. 27,pp 1197-1203. Commercially available software programs may be used toassist in deriving reactivity ratios from experimentally derived data.One example of such software is Aspen Plus from Aspen Technology, Inc.,Ten Canal Park, Cambridge, Mass. 02141-2201, USA. It is often preferredin many copolymer compositions that the amount of alpha-olefin includedbe less than the amount of ethylene, simply for reasons of relative costof the monomers. Thus, it is often, although not always, preferred thatthe target amount of alpha-olefin in a copolymer range from 1 to 30 molepercent (mol %); more preferably from 1 to 25 mol %; and still morepreferably from 0 to 20 mol %.

The metal-ligand complex of formula (I) is rendered catalytically activeby contacting it to, or combining it with, the activating co-catalyst orby using an activating technique such as those that are known in the artfor use with metal-based olefin polymerization reactions. Suitableactivating co-catalysts for use herein include alkyl aluminums;polymeric or oligomeric alumoxanes (also known as aluminoxanes); neutralLewis acids; and non-polymeric, non-coordinating, ion-forming compounds,including but not limited to the use of such compounds under oxidizingconditions. A suitable activating technique may be bulk electrolysis.Combinations of one or more of the foregoing activating co-catalystsand/or techniques are also contemplated. The term “alkyl aluminum” meansa monoalkyl aluminum dihydride or monoalkylaluminum dihalide, a dialkylaluminum hydride or dialkyl aluminum halide, or a trialkylaluminum.Alumoxanes and their preparations are described in, for additionalunderstanding, U.S. Pat. No. 6,103,657. Examples of preferred polymericor oligomeric alumoxanes are methylalumoxane,triisobutylaluminum-modified methylalumoxane, and isobutylalumoxane.Such may be employed such that the ratio of total number of moles of theone or more metal-ligand complexes of formula (I) to total number ofmoles of activating co-catalyst is preferably from 1:10,000 to 100:1.

A variety of homopolymerization or copolymerization conditions andcombinations thereof may be employed, according to the startingmaterials, nature of the reaction (batch, semi-continuous, orcontinuous), apparatus set-up, desired products, and so forth. However,in general, suitable polymers or copolymers of the invention may beproduced using one or more of the specified catalyst selections at atemperature ranging from 20 degrees Celsius (° C.) to 220° C., andpreferably 100° C. to 200° C., for a time preferably ranging from 10minutes (min) to 300 min. Other parameters, such as pressure, may becontrolled within ranges known to those skilled in the art and are notgenerally considered to be critical to practice of the presentinvention, but may be varied according to the desires and needs of thepractitioner. It is usually preferred to carry out the process as acontinuous process, using at least one continuous stir tank reactor(CSTR) or other suitable vessel(s).

The particular advantage of the invention will be apparent whencomparative homopolymers or copolymers are prepared under identicalconditions and using identical starting materials, where the inventiveprocess uses one of the defined catalysts that has at least one halogenlocated in a position that is ortho to the Z moiety as defined, i.e., asthe R^(1a) and/or R^(1b) substituent, and the comparative process uses acatalyst that is otherwise identical but which does not have a halogenat either of those locations. Surprisingly, it has been found thathomopolymers or copolymers produced by the inventive process may have anM_(w) that is reduced by at least 20%, preferably at least 30%, morepreferably at least 40%, and most preferably at least 80%, when comparedwith the homopolymers or copolymers produced using the otherwiseidentical catalyst wherein neither R^(1a) nor R^(1b) is a halogen atom.

Even more surprisingly, it has been further found that homopolymers orcopolymers produced by the inventive process using a catalyst whereinboth of the R^(1a) and R^(1b) substituents are halogen atoms may have anM_(w) that is reduced by at least 20%, preferably at least 30%, morepreferably at least 40%, and most preferably at least 80%, when comparedwith homopolymers or copolymers produced by an otherwise identicalinventive process employing a catalyst having just one halogen in eitherthe R^(1a) or the R^(1b) position.

Thus, in certain embodiments, use of a catalyst including the onestrategically located halogen in the ortho position may surprisinglyproduce a homopolymer or copolymer having a molecular weight that is aslow as one-fifth that produced using an otherwise identical catalystwith no halogens at either ortho position, while use of a catalystincluding two halogens in those ortho positions may surprisingly producea homopolymer or copolymer having a molecular weight that is as low asone-tenth that produced using the otherwise identical catalyst with nohalogens at either ortho position. In view of this, the inventiveprocess enables a way to predictably reduce the weight average molecularweight (M_(w)) of the homopolymer or copolymer produced, which meansthat rheological behavior is modified and the processability andapplications of the homopolymer or copolymer may also be modified inways that may be desirable. At the same time, most other properties ofthe resulting homopolymer or copolymer are not comparably affected,although where an ethylene/alpha-olefin copolymer is being prepared, theamount of alpha-olefin incorporation may in some cases be somewhatreduced by the presence of a halogen atom at the R^(1a), R^(1b), or bothpositions.

EXAMPLES 1-6 AND COMPARATIVE EXAMPLES A-D

A series of catalysts having the chemical names and formula structuresshown hereinbelow is used to carry out ethylene/1-octenecopolymerizations.

Catalyst 1 is(2′,2″-(propane-1,3-diylbis(oxy))bis(3-(3,6-di-tert-butyl-9H-carbazol-9-yl)-5′-fluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for Comparative Example (CEx.) A.

Catalyst 2 is2′,2″-(propane-1,3-diylbis(oxy))-1-(3,6-di-tert-butyl-9H-carbazol-9-yl)-5′-fluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)-3-(3,6-di-tert-butyl-9H-carbazol-9-yl)-3′,5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for Example (Ex.) 1.

Catalyst 3 is(2′,2″-(propane-1,3-diylbis(oxy))bis(3-(3,6-di-tert-butyl-9H-carbazol-9-yl)-3′,5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for Ex. 2.

Catalyst 4 is(2′,2″-(propane-1,3-diylbis(oxy))bis(3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5′-fluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for CEx. B.

Catalyst 5 is2′,2″-(propane-1,3-diylbis(oxy))-1-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5′-fluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)-3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′,5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for Ex, 3.

Catalyst 6 is2′,2″-(propane-1,3-diylbis(oxy))-1-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5′-fluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)-3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′-methyl-5′-fluoro-5-(2,4,4-trimethyl-pentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for CEx. C.

Catalyst 7 is2′,2″-(propane-1,3-diylbis(oxy))-1-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′-5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)-3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′-methyl-5′-fluoro-5-(2,4,4-trimethyl-pentan-2-yl)biphenyl-2-ol)dimethyl-hafnium.It is used for Ex. 4.

Catalyst 8 is(2′,2″-(propane-1,3-diylbis(oxy))bis(3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′-methyl-5′-fluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-zirconium.It is used for CEx. D.

Catalyst 9 is(2′,2″-(propane-1,3-diylbis(oxy))bis(3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′-5′-dichloro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-zirconium.It is used for Ex. 5.

Catalyst 10 is(2′,2″-(propane-1,3-diylbis(oxy))bis(3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)biphenyl-2-ol)dimethyl-zirconium.It is used for Ex. 6.

Each of the prepared catalysts is used to prepare an ethylene/octenecopolymer by the following procedure. A 2 liter (L) Parr reactor is usedin the polymerizations. All feeds are passed through columns of aluminaand Q-5™ catalyst (available from Engelhard Chemicals Inc.) prior tointroduction into the reactor. Catalyst and cocatalyst (activator)solutions are handled in the glove box. A stirred 2 L reactor is chargedwith about 605 grams (g) of mixed alkanes solvent and 300 g of 1-octenecomonomer. The reactor contents are heated to the polymerizationtemperature of 140° C. and saturated with ethylene at 288 pounds persquare inch gauge (psig, ˜1.99 megapascals, MPa). Catalysts andcocatalysts, as dilute solutions in toluene, are mixed and transferredto a catalyst addition tank and injected into the reactor. Thepolymerization conditions are maintained for 10 minutes (min) withethylene added on demand. Heat is continuously removed from the reactionvessel through an internal cooling coil. The resulting solution isremoved from the reactor, quenched with isopropyl alcohol, andstabilized by addition of 10 milliliters (mL) of a toluene solutioncontaining approximately 67 milligrams (mg) of a hindered phenolantioxidant (Irganox™ 1010 from Ciba Geigy Corporation) and 133 mg of aphosphorus stabilizer (Irgafos™ 168 from Ciba Geigy Corporation).Between polymerization runs, a wash cycle is conducted in which 850 g ofmixed alkanes is added to the reactor and the reactor is heated to 150°C. The reactor is then emptied of the heated solvent immediately beforebeginning a new polymerization run. Polymers are recovered by drying forabout 12 hours (h) in a temperature-ramped vacuum oven with a final setpoint of 140° C.

Polymer characterization is then carried out. Melting andcrystallization temperatures of polymers are measured by differentialscanning calorimetry (DSC 2910, TA Instruments, Inc.). Samples are firstheated from room temperature to 180° C. at a ramp rate of 10° C./min.After being held at this temperature for 2 to 4 min, the samples arecooled to −40° C. at 10° C./min, held for 2 to 4 min, and then heated to160° C. Molecular weight distribution (Mw, Mn) information is determinedby analysis on a Robotic-Assisted Dilution High-Temperature GelPermeation Chromatograph (RAD-GPC). Polymer samples are dissolved for 90min at 160° C. at a concentration of 30 mg/mL in 1,2,4-trichlorobenzene(TCB) stabilized by 300 parts per million (ppm) of butylatedhydroxytoluene (BHT) in capped vials while stirring. They are thendiluted to 1 mg/mL immediately before a 400 microliter (μL) aliquot ofthe sample is injected. The GPC utilizes two (2) POLYMER LABS™ PLgel™ 10μm MIXED-B columns (300 millimeter (mm)×10 mm) at a flow rate of 2.0mL/min at 150° C. Sample detection is performed using a POLYMER CHAR™IR4 detector in concentration mode. A conventional calibration of narrowPolystyrene (PS) standards is utilized, with apparent units adjusted tohomo-polyethylene (PE) using known Mark-Houwink coefficients for PS andPE in 1,2,3-trichlorobenzene (TCB) at this temperature. Absolute Mwinformation is calculated using a polydispersity index (PDI) staticlow-angle light scatter detector. To determine octene incorporation, 140μL of each polymer solution is deposited onto a silicon wafer, heated at140° C. until the TCB has evaporated and analyzed using a Nicolet Nexus670 Fourier transform infrared (FTIR) spectroscopy apparatus with 7.1version software equipped with an AUTOPRO™ auto sampler. Results areshown in Table 1.

TABLE 1 Polymerization Results^(a) Ex. Efficiency or Catalyst Yield(gPoly/ Octene CEx. # μmoles Metal (g) gMetal) Mw Mw/Mn mol % CEx. 10.055 Hf 35.3 3,595,822 554,019 2.17 29.9 A Ex. 1 2 0.08 Hf 22.31,561,712 105,743 2.30 13.7 Ex. 2 3 0.15 Hf 50.7 1,893,664 25,607 2.528.7 CEx. 4 0.055 Hf 12 1,222,376 209,430 2.11 18.4 B Ex. 3 5 0.02 Hf16.2 4,538,069 148,247 2.44 5.8 Cex. 6 0.03 Hf 17.7 3,305,507 692,5322.69 4.0 C Ex. 4 7 0.02 Hf 11.9 3,333,520 339,431 2.19 1.2 Cex. 8 0.01Zr 28.7 31,461,019 198,051 2.90 0.0 D Ex. 5 9 0.02 Zr 28.8 15,785,32042,020 3.22 2.2 Ex. 6 10 0.06 Zr 40.7 7,435,909 21,870 3.18 4.2^(a)Polymerization conditions: 2 L batch reactor, 605 mL of Isopar ™-E;temp = 140° C.; 300 g of 1-octene; ethylene pressure = 288 psi;catalyst:activator = 1:1.2; activator; [HNMe(C₁₈H₃₇)₂][B(C₆F₅)₄]; 1:10MMAO; reaction time 10 min.

It is noted that reduction of the molecular weight via use of thesingle- (Catalyst 2, 5, and 7) or double-halogenated (Catalyst 3, 9, and10) [at the ortho position(s)] catalysts also proportionately reducesoctene incorporation into the copolymer when compared with copolymersprepared using non-halogenated [at the ortho position(s)] catalysts(Catalyst 1, 4, 6, and 8). Furthermore, halogenation with fluorine atomsappears to be more effective in these examples than halogenation withchlorine atoms.

EXAMPLE 7

This Ex. 7 illustrates a sample catalyst preparation. Those skilled inthe art will understand that similar and analogous methods may becarried out to prepare other catalysts suitable for use in the presentinvention. Confirmation of each product is carried out by ¹H NMR and ¹⁹FNMR.

(a) Step 1: Preparation of 2-(3-bromopropoxy)-1,5-difluoro-3-iodobenzene

A mixture of 2-iodo-4,6-difluorophenol (10.00 g, 38.28 millimoles(mmol)) [prepared according to WO/2012/027448], 1,3-dibromopropane (155g, 765 mmol), potassium carbonate (10.582 g, 76.566 mmol), and acetone(250 mL) is heated to reflux for 1 h. The mixture is allowed to cool toroom temperature and concentrated. The residue is partitioned in a 50/50methylene chloride/water mixture and extracted with methylene chloride.The combined organic phases are washed with 2 N NaOH (300 mL), brine(300 mL), water (300 mL), dried over MgSO₄, filtered through a pad ofsilica gel and concentrated. The resulting oil is purified via columnchromatography using a hexanes:ethyl acetate gradient to afford 12.5 g(86.8%) of the product as a slightly yellow oil. As used herein,“hexanes” refers to a commercially obtained mixture of hexane isomers.

(b) Step 2: Preparation of1,5-difluoro-2-(3-(4-fluoro-2-iodophenoxy)propoxy)-3-iodobenzene

A mixture of 2-(3-bromopropoxy)-1,5-difluoro-3-iodobenzene (4.00 g, 10.6mmol), 2-iodo-4-fluorophenol (2.525 g, 10.61 mmol) [prepared accordingto WO/2012/027448], potassium carbonate (3.094 g, 22.39 mmol), andacetone (80 mL) is heated to reflux and allowed to stir overnight. Themixture is cooled to room temperature and filtered. The cake is washedwith acetone. The filtrate is concentrated to afford the crude as darkbrown oil which is purified by column chromatography using 5% ethylacetate in hexanes to afford 3.69 g (65.1%) of the product as acolorless oil.

(c) Step 3: Preparation of3-(3,6-di-tert-butyl-9H-carbazol-9-yl)-2′-(3-((3′-(3,6-di-tert-butyl-9H-carbazol-9-yl)-5-fluoro-2′-hydroxy-5′-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-yl)oxy)propoxy)-3′,5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-ol

A mixture of 1,2-dimethoxyethane (69 mL),3,6-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carba-zole(4.00 g, 5.71 mmol) [prepared according to US2011/0282018],1,5-difluoro-2-(3-(4-fluoro-2-iodophenoxy)propoxy)-3-iodobenzene (1.524g, 2.711 mmol), a solution of NaOH (0.6849 g, 17.12 mmol) in water (16mL) and tetrahydrofuran (THF) (40 mL) is purged with nitrogen (N₂) for15 min, then Pd(PPh₃)₄ ((Ph=phenyl, 0.1318 g, 0.1142 mmol) is added andheated to 85° C. overnight. The mixture is allowed to cool to roomtemperature and concentrated. The residue is taken up in methylenechloride (200 mL), washed with brine (200 mL), dried over anhydrousMgSO₄, filtered through a pad of silica gel, and concentrated to affordthe crude protected ligand. To the crude is added THF (50 mL), methanol(MeOH, 50 mL) and approximately 100 mg of p-toluenesulfonic acidmonohydrate (PTSA). The solution is heated to 60° C. overnight, thencooled and concentrated. To the crude ligand is added methylene chloride(200 mL), washed with brine (200 mL), dried over anhydrous MgSO₄,filtered through a pad of silica gel, and concentrated to afford a browncrystalline powder. The solid is purified by column chromatography usinga gradient of methylene chloride:hexanes to afford 1.77 g (52.4%) of theproduct as a white solid.

(d) Step 4: Formation of Metal-Ligand Complex

To a mixture of HfCl₄ (0.117 g, 0.37 mmol) and ligand (0.4573 g, 0.37mmol) suspended in toluene (4 mL) is added 3M MeMgBr (Me=methyl, 0.52mL, 1.56 mmol) in diethyl ether. After stirring for 1 hr at roomtemperature, hexane (10 mL) is added and the suspension is filtered,giving colorless solution. Solvent is removed under reduced pressure togive 0.4125 g (77.4%) of product metal-ligand complex.

EXAMPLE 8

Catalyst 4 is prepared as follows:

(a) Step 1: Preparation of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole

A mixture of2-(2-iodo-4-(2,4,4-trimethylpentan-2-yl)phenoxy)tetrahydro-2H-pyran(21.74 g, 52.22 mmol) [prepared according to WO/2012/027448],2,7-di-tert-butylcarbazole (8.03 g, 28.73 mmol) [prepared according to(need full citation here) Synthesis 1979, 49-50], K₃PO₄ (23.40 g, 110.24mmol), anhydrous CuI (0.22 g, 1.16 mmol), dry toluene (85 mL) andN,N′-dimethylethylenediamine (0.45 mL, 4.18 mmol) is heated to 125° C.After 24 h, additional anhydrous CuI (0.2 g, 1.05 mmol) slurry in drytoluene (0.9 mL) and N,N′-dimethylethylenediamine (0.45 mL, 4.18 mmol)is added and stirring is continued at 125° C. for an additional 72 h.After 96 h, the reaction is allowed to cool to room temperature andfiltered through a small silica plug, washed with THF and concentratedto give the crude product as a dark brown oil. The crude is crystallizedfrom hot hexanes (50 mL) to afford 13.48 g (90.9%) of the product as anoff-white powder.

(b) Step 2: Preparation of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole

A solution of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-5-(2,4,4-trimethylpentan-2-yl)-phenyl)-9H-carbazole(7.70 g, 13.56 mmol) and dry THF (90 mL) under N₂ atmosphere is cooledto 0-10° C. (ice-water bath) and 2.5 molar (M) n-BuLi (Bu=butyl) inhexanes (14.0 mL, 35.0 mmol) is added slowly. After 4 hr,2-iso-propoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (7.0 mL, 34.3mmol) is added slowly. The mixture is stirred for 1 h at 0-10° C. beforeallowing the reaction to warm to room temperature and then stirred foran additional 18 h. To the reaction mixture is added cold saturatedaqueous sodium bicarbonate (75 mL) and then the mixture is extractedwith four 50-mL portions of methylene chloride. The combined organicphases are washed with cold saturated aqueous sodium bicarbonate (200mL), brine (200 mL), dried over anhydrous MgSO₄, filtered andconcentrated to give the crude as a golden foam. This crude is slurriedin acetonitrile (75 mL) and allowed to sit for 1 h at room temperature.The solid is isolated, washed with a small portion of cold acetonitrileand dried under high vacuum to afford 8.12 g (86.3%) of the product as awhite powder.

(c) Step 3: Preparation of6′,6″′-(propane-1,3-diylbis(oxy))bis(3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3′-fluoro-5-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-ol)

A mixture of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(4.00 g, 5.24 mmol adjusted based on a purity of 90.9% by highperformance liquid chromatography, HPLC), 1,2-dimethoxyethane (65 mL), asolution of NaOH (0.67 g, 17.25 mmol) in water (19 mL), THF (22 mL), and1,3-bis(4-fluoro-2-iodophenoxy)propane (1.28 g, 2.49 mmol) [preparedaccording to WO/2012/027448] is purged with N₂ for approximately 15 min.Then, Pd(PPh₃)₄ (202 mg, 0.18 mmol) is added and heated to reflux. After48 h, the mixture is allowed to cool to room temperature. Theprecipitate is isolated and dried under high vacuum for about 1 h toafford the crude protected ligand. The crude is dissolved in a mixtureof THF (100 mL) and MeOH (100 mL) and then heated to 60° C. To thesolution is added PTSA until the solution becomes acidic (measured viapH paper), then it is stirred at 60° C. for 8 h and then allowed tocool. The precipitate is isolated by vacuum filtration, rinsed with coldacetonitrile (25 mL) and dried to afford about 1 g of ligand. Meanwhile,the filtrate develops a precipitate which is isolated and dried underhigh vacuum to afford approximately 1 additional g of ligand. The cropsare combined using chloroform (50 mL) and concentrated to afford 2.37 g(77.6%) of ligand as white powder.

(d) Step 4: Formation of Metal-Ligand Complex

To a cold (−30° C.) toluene solution (40 mL) of ligand (0.545 g, 0.44mmol) and HfCl₄ (0.142 g, 0.44 mmol) is added 3 M MeMgBr in diethylether (0.64 mL, 1.92 mmol). After stirring for 2 h, the black suspensionis filtered using medium glass frit giving colorless solution. Solventis removed under reduced pressure giving 0.589 g (92.5%) of product.

EXAMPLE 9 (a) Step 1: Preparation of3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-2′-(3-((3′-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5-fluoro-2′-hydroxy-5′-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-yl)oxy)propoxy)-3′,5′-difluoro-5-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-ol

A mixture of 1,2-dimethoxyethane (69 mL),2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(4.00 g, 5.708 mmol),1,5-difluoro-2-(3-(4-fluoro-2-iodophenoxy)propoxy)-3-iodobenzene (1.524g, 2.711 mmol), a solution of NaOH (0.6849 g, 17.12 mmol) in water (16mL) and THF (40 mL) is purged with N₂ for 15 min, then Pd(PPh₃)₄ (0.1318g, 0.1142 mmol) is added and heated to 85° C. overnight, then cooled. Tothe residue is added methylene chloride (200 mL), then it is washed withbrine (200 mL), dried over anhydrous MgSO₄, filtered through a pad ofsilica gel, and concentrated to afford the crude protected ligand. Tothe crude is added THF (50 mL), MeOH (50 mL) and approximately 100 mg ofPTSA, added until acidic solution by pH paper. The solution is heated to60° C. overnight, then cooled and concentrated. To the crude mixture isadded methylene chloride (200 mL), it is washed with brine (200 mL),dried over anhydrous MgSO₄, filtered through a pad of silica gel, andconcentrated to afford a brown crystalline powder. The crude is purifiedvia column chromatography, eluting with a methylene chloride:hexanesgradient to afford 2.63 g (81.2%) of the ligand as a white solid.

(b) Step 2: Formation of Metal-Ligand Complex

To a cold (−25° C.) slurry of HfCl₄ (0.1038 g, 0.3241 mmol) in toluene(20 mL) is added 3.0 M MeMgBr in diethyl ether (0.45 mL, 1.35 mmol) andagitated vigorously for 2 min. To the mixture is added the ligand(0.4022 g, 0.3229 mmol) as a solid using toluene (3.0 mL) to rinse. Thebrown mixture is stirred for 2 h at room temperature, then hexanes (20mL) is added and the mixture is filtered. The filtrate, a colorlesssolution, is concentrated under high vacuum. To the solid is addedhexanes (10 mL) and stirred for about 10 min. The off-white solid iscollected by filtration and dried under high vacuum to afford 0.4112 g(87.7%) of the product.

EXAMPLE 10 (a) Step 1: Preparation of1-(3-bromopropoxy)-4-fluoro-2-iodobenzene

A mixture of 4-fluoro-2-iodophenol (7.0020 g, 29.420 mmol), potassiumcarbonate (8.2954 g, 60.020 mmol), 1,3-dibromopropane (59.00 mL, 581.262mmol), and acetone (200 mL) is stirred and refluxed overnight. After16.5 h, the reaction is allowed to cool to room temperature and filteredby vacuum filtration. The solids are washed with acetone (2×20 mL) andfiltered as well. The filtrate is concentrated and the yellow solutionthat remains is distilled under vacuum to remove the remaining1,3-dibromopropane. The crude brown oil is dissolved in a small amountof hexanes and is purified by column chromatography using a gradient of0-5% ethyl acetate in hexanes to afford 8.99 g (85.1%) of the product asa yellow oil.

(b) Step 2: Preparation of5-fluoro-2-(3-(4-fluoro-2-iodophenoxy)propoxy)-1-iodo-3-methylbenzene

A mixture of 1-(3-bromopropoxy)-4-fluoro-2-iodobenzene (8.9856 g, 25.032mmol), 4-fluoro-2-iodo-6-methylphenol (6.3096 g, 25.036 mmol), potassiumcarbonate (7.400 g, 53.542 mmol), and acetone (165 mL) is stirred andrefluxed overnight. After 16 h, the reaction is allowed to cool to roomtemperature and filtered by vacuum filtration. The solids are washedwith acetone (2×20 mL) and filtered as well. The filtrate isconcentrated to afford the crude product as dark brown oil. The oil isdissolved in a small amount of hexanes and is purified by columnchromatography using a gradient of 0-5% ethyl acetate in hexanes toafford 11.55 g (87.1%) of the product as a yellow solid.

(c) Step 3: Preparation of3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-2′-(3-((3′-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5-fluoro-2′-hydroxy-5′-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-yl)oxy)propoxy)-5′-fluoro-3′-methyl-5-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-ol

A mixture of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(9.4182 g, 13.575 mmol), 1,2-DME (170 mL), a solution of NaOH (1.8145 g,45.438 mmol) in water (49 mL), THF (57 mL), and5-fluoro-2-(3-(4-fluoro-2-iodophenoxy)propoxy)-1-iodo-3-methylbenzene(3.4233 g, 6.458 mmol) is stirred and purged with N₂ for approximately15 min, then Pd(PPh₃)₄ (0.5432 g, 0.470 mmol) is added. The mixture isheated to reflux for 19 h and allowed to cool to room temperature. Thephases are separated and the organic phase is dried over anhydrousMgSO₄, filtered, and concentrated to afford a foamy golden orange solidas a crude protected ligand. The crude is dissolved in a mixture of THF(250 mL) and MeOH (250 mL), then heated to 60° C. To the solution isadded PTSA (3.0380 g, 15.971 mmol) until the solution becomes acidic.The reaction is stirred at 60° C. overnight, then allowed to cool toroom temperature, and concentrated to afford a brown sticky solid. Thecrude product is dissolved in chloroform and silica gel is added. Theslurry is concentrated to afford a dry powdery mixture which is purifiedby flash column chromatography using a gradient of 2-5% ethyl acetate inhexanes to afford the product as a light yellow crystalline solid. Toremove traces of ethyl acetate, the solid is dissolved indichloromethane and concentrated to afford a light yellow crystallinesolid (repeated twice). The solid is dried under high vacuum to afford6.17 g (77.0%).

(d) Step 3: Formation of Metal-Ligand Complex

To a cold (−25° C.) slurry of HfCl₄ (0.1033 g, 0.3225 mmol) and toluene(20 mL) is added 3.0 M MeMgBr in diethyl ether (0.45 mL, 1.35 mmol) andagitated vigorously for 2 min. To the mixture is added the ligand(0.4000 g, 0.3221 mmol) as a solid, rinsing with toluene (2.0 mL). Afterstirring for 1.5 h, the reaction mixture is filtered using a frittedmedium funnel. The cake is washed with two 10-mL portions of toluene. Tothe colorless filtrate is added hexanes (5 mL) and concentrated undervacuum to afford a white solid. To the solid is added toluene (30 mL)and stirred until almost all of the solid goes into solution. Thenhexanes (25 mL) is added. The cloudy yellowish solution is filtered(syringe filter) and concentrated under high vacuum to afford 0.4317 gof product as a tan colored solid.

EXAMPLE 11 (a) Step 1: Preparation of2-(3-(2,4-difluoro-6-iodophenoxy)propoxy)-5-fluoro-1-iodo-3-methylbenzene

A mixture of 2-(3-bromopropoxy)-1,5-difluoro-3-iodobenzene (4.00 g,10.61 mmol), 4-fluoro-2-iodo-6-methylphenol (2.674 g, 10.61 mmol)[prepared according to US2011/0282018], potassium carbonate (3.094 g,22.39 mmol), and acetone (80 mL) is heated to reflux and allowed to stirovernight. The reaction is cooled to room temperature, filtered, washedsolids with acetone, and concentrated to afford a dark brown oil. Theoil is mixed with acetonitrile and allowed to crystallize in thefreezer. After filtration, the brown solid is vacuum dried to afford4.47 g (76.9%) of the product.

(b) Step 2: Preparation of3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-2′-(3-((3′-(2,7-di-tert-butyl-9H-carbazol-9-yl)-3,5-difluoro-2′-hydroxy-5′-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-yl)oxy)propoxy)-5′-fluoro-3′-methyl-5-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-ol

A mixture of 1,2-dimethoxyethane (60 mL) is added2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(3.50 g, 4.69 mmol),2-(3-(2,4-difluoro-6-iodophenoxy)propoxy)-5-fluoro-1-iodo-3-methylbenzene(1.246 g, 2.228 mmol), a solution of NaOH (0.563 g, 14.08 mmol) in water(14 mL) and THF (35 mL) is purged with N₂ for 15 min, then Pd(PPh₃)₄(0.1083 g, 0.0983 mmol) is added and heated to 85° C. overnight. Themixture is allowed to cool and methylene chloride (200 mL) is added,then washed with brine (200 mL), dried over anhydrous MgSO₄, filteredthrough a pad of silica gel, and concentrated to afford the crudeprotected ligand. To the crude is added THF (50 mL), MeOH (50 mL) andabout 100 mg of PTSA until the solution is acidic by pH paper. Thesolution is heated to 60° C. overnight, then cooled and concentrated. Tothe crude is then added methylene chloride (200 mL), washed with brine(200 mL), dried over anhydrous MgSO₄, filtered through a pad of silicagel, and concentrated to afford a brown crystalline powder. The solid ispurified by two flash column chromatography elutions with a gradient ofhexanes:ethyl acetate for the first column and a gradient of methylenechloride:hexanes for the second column to afford 1.42 g (50.6%) of theligand as white crystals.

(c) Step 3: Formation of the Metal-Ligand Complex

To a cold (−25° C.) slurry of HfCl₄ (0.1031 g, 0.3219 mmol) and toluene(20 mL) is added 3.0 M MeMgBr in diethyl ether (0.45 mL, 1.35 mmol). Themixture is vigorously agitated for 2 min and the ligand (0.4012 g,0.3185 mmol) is added as a solid, rinsing with toluene (3.0 mL). Thereaction mixture is stirred at room temperature for 2 h. To theyellowish mixture is added a mixture of hexanes (20 mL) and filtered.The filtrate, a colorless solution, is concentrated under high vacuum.To the solid is added the mixture of hexanes (10 mL) and stirred forabout 10 min. The solid is collected by filtration and dried to afford amixture of the desired product and a minor component attributed toinsufficient alkylation. The filtrate is concentrated and re-combinedwith the solid. The mixture is dissolved in toluene (15 mL) and 3.0 MMeMgBr (0.10 mL, 0.30 mmol) is added. The mixture is stirred for 1 h,filtered and concentrated. The brown solid is dissolved in toluene (15mL), and the hexanes are added (25 mL). The cloudy solution is filteredand concentrated to give a tan colored solid. To the solid is added themixture of hexanes (30 mL) and agitated vigorously for 1 h. The whitesolid is collected and dried under high vacuum to afford 0.2228 g(47.7%) of the product.

EXAMPLE 12 (a) Step 1: Preparation of2′,2″′-(propane-1,3-diylbis(oxy))bis(3-(2,7-di-tert-butyl-9H-carbazol-9-yl)-5′-fluoro-3′-methyl-5-(2,4,4-trimethylpentan-2-yl)-[1,1′-biphenyl]-2-ol)

A mixture of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(7.52 g, 9.89 mmol adjusted based on a purity of 91.2% by HPLC),1,2-dimethoxyethane (120 mL), a solution of NaOH (1.30 g, 32.5 mmol) inwater (35 mL), THF (60 mL), and1,3-bis(4-fluoro-2-iodo-6-methylphenoxy)propane (2.56 g, 4.70 mmol)[prepared according to US 2011/0282018] is purged with N₂ forapproximately 15 minutes and Pd(PPh₃)₄ (303 mg, 0.26 mmol) is added. Themixture is heated to reflux for 48 h, then allowed to cool to roomtemperature. Once cooled a precipitate is formed which is isolated anddried under high vacuum for 1 h to afford 6.10 g of crude protectedligand. To the crude is added a mixture of 1:1 MeOH/THF (200 mL) andapproximately 100 mg of PTSA. The solution is heated at 60° C. for 8 h,then allowed to cool and concentrated. To the residue is added methylenechloride (250 mL), washed with brine (250 mL), dried over anhydrousMgSO₄, filtered through a pad of silica gel, then concentrated to afford4.92 g of crude ligand. This crude is purified by flash chromatographyeluting with 2% ethyl acetate in hexanes to afford 4.23 g (71.7%) ofproduct as white powder.

(b) Step 2: Formation of Metal-Ligand Complex

To a cold (−30° C.) toluene solution (30 mL) of ligand and ZrCl₄ isadded 3M MeMgBr in diethyl ether (4.1 mL, 12.3 mmol). After stirringovernight, the black suspension is filtered using a medium glass frit,giving a colorless solution. Solvent is removed under reduced pressure,giving 0.456 g (61.7%) of product as white solid.

EXAMPLE 13 (a) Step 1: Preparation of Ligand

A mixture of2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(3.50 g, 5.16 mmol), 1,2-dimethoxyethane (200 mL), a solution of NaOH(0.62 g, 15.47 mmol) in water (60 mL), THF (60 mL), and1,3-bis(2,4-dichloro-6-iodophenoxy)propane (1.51 g, 2.45 mmol) [preparedaccording to US 2011/0282018] is purged with N₂ for approximately 15 minand Pd(PPh₃)₄ (0.12 g, 0.10 mmol) is added. The mixture is heated toreflux for 48 h, then allowed to cool and concentrated. To the residueis added methylene chloride (200 mL), washed with brine (200 mL), driedover anhydrous MgSO₄, filtered through a pad of silica, and concentratedto afford the crude protected ligand. The crude is dissolved in amixture of THF (100 mL) and MeOH (100 mL), heated to 60° C. and PTSA isadded until the solution becomes acidic (pH paper). The mixture isstirred at 60° C. for 8 h, then allowed to cool to room temperature andconcentrated. To the residue is added methylene chloride (200 mL),washed with brine (200 mL), dried over anhydrous MgSO₄, filtered througha pad of silica gel, and concentrated to give the crude ligand. Thecrude is purified via flash chromatography eluting with 40% methylenechloride in hexanes to afford 2.57 g (78.9%) of the ligand as a whitepowder.

(b) Step 2: Formation of Metal-Ligand Complex

To cold toluene (20 mL) containing ZrCl₄ (0.105 g, 0.45 mmol) is added3.0 M MeMgBr in diethyl ether (0.63 mL, 1.90 mmol). After stirring for 3min, the ligand (0.60 g, 0.45 mmol) is added as a solid. After stirringfor 2 h, hexanes (20 mL) is added and the black suspension is filtrated.Solvent is removed under reduced pressure, giving an off-white solid. Tothis solid is added hexanes (20 mL) and stirred for 10 min. Product iscollected on the frit, washed with hexanes (5 mL) and dried underreduced pressure to give (0.5032 g, 77%) of white solid.

EXAMPLE 14

Preparation of the Fluoro Analog of Catalyst 9:

(a) Step 1: Preparation of the Ligand

A mixture of 1,2-dimethoxyethane (50 mL),2,7-di-tert-butyl-9-(2-((tetrahydro-2H-pyran-2-yl)oxy)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5-(2,4,4-trimethylpentan-2-yl)phenyl)-9H-carbazole(3.068 g, 4.17 mmol), 1,3-bis(2,4-difluoro-6-iodophenoxy)propane (1.05g, 1.98 mmol) [prepared according to US 2011/0282018], a solution ofNaOH (0.56 g, 14.0 mmol) in water (14 mL), and THF (14 mL) is purgedwith N₂ for about 15 min, then Pd(PPh₃)₄ (145 mg, 0.13 mmol) is added.The reaction mixture is heated to 85° C. for 36 h, then cooled. Oncecooled a precipitate is formed which is isolated and dried under highvacuum for 2 h, resulting in crude protected ligand. To the crude isadded a 1:1 mixture of THF:MeOH (50 mL) and approximately 100 mg ofPTSA. The solution is heated to 60° C. for 8 h, then cooled andconcentrated. To the residue is added methylene chloride (200 mL),washed with brine (200 mL), dried over anhydrous MgSO₄, filtered througha pad of silica gel, and concentrated. The residue is dissolved inhexanes and purified by flash column chromatography using a gradient of2-5% ethyl acetate in hexanes to afford 1.80 g (72.0%) of the product asa white powder.

(b) Step 2: Formation of Metal-Ligand Complex

To cold toluene (30 mL) containing ZrCl₄ (0.055 g, 0.24 mmol) is added3.0 M MeMgBr in diethyl ether (0.33 mL, 1.0 mmol). After stirring for 5min, the ligand (0.300 g, 0.24 mmol) is added as a solid. After stirringfor 1 h, an amount of hexane (15 mL) is added and the black suspensionis filtrated. Solvent is removed under reduced pressure, giving 0.312 g(85.6%) of product as white solid.

The invention claimed is:
 1. A process for preparing an olefinhomopolymer or copolymer, comprising contacting ethylene, analpha-olefin, or a combination thereof, and a catalytic amount of ametal-ligand complex catalyst of the formula (I):

where M is titanium, zirconium, or hafnium and has a formal oxidationstate of +2, +3, or +4; n is 0, 1, or 2; when n is 1, X is a monodentateligand or a bidentate ligand; when n is 2, each X is an independentlychosen monodentate ligand; the metal-ligand complex is overallcharge-neutral; each Z is independently chosen from —O—, —S—,—N(R^(N))—, or —P(R^(P))—; L is (C₁-C₄₀)hydrocarbylene or(C₁-C₄₀)heterohydrocarbylene, provided such has a portion that comprisesa 2- to 8-carbon atom linker backbone linking the Z moieties, each atomof such 2- to 8-atom linker being independently a carbon atom or aheteroatom, wherein each heteroatom independently is O, S, S(O), S(O)₂,Si(R^(C))₂, Ge(R^(C))₂, P(R^(P)), or N(R^(N)), wherein independentlyeach R^(C) is unsubstituted (C₁-C₁₈)hydrocarbyl or the two R^(C) aretaken together to form a (C₂-C₉)alkylene, each R^(P) is unsubstituted(C₁-C₁₈)hydrocarbyl; and each R^(N) is unsubstituted(C₁-C₁₈)hydrocarbyl, or a hydrogen atom; R^(1a) and R^(1b) areindependently a halogen atom or a hydrogen atom, provided that at leastone of R^(1a) and R^(1b) is a halogen atom; R^(2a), R^(3a), R^(4a),R^(2b), R^(3b), R^(4b), R^(6c), R^(7c), R^(8c), R^(6d), R^(7d), andR^(8d) independently is a hydrogen atom; (C₁-C₄₀)hydrocarbyl;(C₁-C₄₀)heterohydrocarbyl; Si(R^(C))₃, Ge(R^(C))₃, P(R^(P))₂, N(R^(N))₂,OR^(C), SR^(C), NO₂, CN, F₃C, F₃CO, RCS(O)—, RCS(O)₂—, (RC)₂C═N—,RCC(O)O—, RCOC(O)—, RCC(O)N(R)—, (RC)₂NC(O)—, or halogen atom; andR^(5c) and R^(5d) independently is independently selected from:phenanthren-9-yl; 2,3-dihydro-1H-inden-6-yl; naphthalene-2-yl;2,6-diethylphenyl; 2,6-diphenyl-phenyl; 3,5-dimethylphenyl;3,5-bis(tri-fluoromethyl)phenyl; 3,5-bis(1-methylethyl)phenyl;2,4,6-trimethylphenyl; and 2,4,6-tris(1-methylethyl)phenyl);1-methyl-2,3-dihydro-1H-inden-6-yl;1,1-dimethyl-2,3-dihydro-1H-inden-6-yl;1-methyl-1,2,3,4-tetrahydro-naphthalen-5-yl;1,1-dimethyl-1,2,3,4-tetrahydronaphthalen-5-yl;3,6-di(tertiary-octyl)-carbazolyl; 3,6-di(tertiary-octyl)-carbazol-9-yl;3,6-diphenylcarbazol-9-yl; 3,6-bis(2,4,6-trimethylphenyl)-carbazol-9-yl;quinolin-4-yl; quinolin-5-yl; quinolin-8-yl;1,2,3,4-tetrahydroquinolin-1-yl; isoquinolin-1-yl; isoquinolin-4-yl;isoquinolin-5-yl; isoquinolin-8-yl; 1,2,3,4-tetrahydroisoquinolin-2-yl;1H-indol-1-yl; 1H-indolin-1-yl; 1,2,3,4-tetrahydrocarbazolyl-9-yl;1,2,3,4,5,6,7,8-octahydrocarbazolyl-9-yl;4,6-bis(1,1-dimethylethyl)pyridine-2-yl; 4,6-diphenylpyridin-2-yl;3-phenyl-1H-indol-1-yl; 3-(1,1-dimethylethyl)-1H-indol-1-yl;3,6-diphenyl-9H-carbazol-9-yl; 3,6-di(1-methylethyl)-9H-carbazol-9-yl;3,6-dimethyl-9H-carbazol-9-yl; 3,6-diethyl-9H-carbazol-9-yl;3,6-bis[2′,4′,6′-tris(1,1-dimethylphenyl)]-9H-carbazol-9-yl;3,6-di(tertiary-butyl)-carbazol-9-yl, provided that when R^(5c) andR^(5d) are 3,6-di(tertiary-butyl)-carbazol-9-yl, R^(1a) or R^(1b) is —H;under conditions such that an ethylene homopolymer, an alpha-olefinhomopolymer, or an ethylene/alpha-olefin copolymer is formed, suchhaving a weight average molecular weight that is reduced by at least 20percent when compared with an otherwise identical ethylene homopolymer,alpha-olefin homopolymer or ethylene/alpha-olefin copolymer preparedunder identical conditions with a catalyst that is otherwise identicalbut wherein neither R^(1a) nor R^(1b) is a halogen atom.
 2. The processof claim 1 wherein R^(1a), R^(1b), or both is independently a halogenatom chosen from fluorine, chlorine, or iodine.
 3. The process of claim1 wherein the alpha-olefin is selected from the group consisting of (A)linear alpha-olefins having from 3 to 12 carbons, (B) branchedalpha-olefins having from 5 to 16 carbons, and both (A) and (B).
 4. Theprocess of claim 1, wherein R^(2a), R^(2b), R^(3a), R^(3b), R^(4a),R^(4b) are hydrogen.
 5. A process for preparing an olefin homopolymer orcopolymer, comprising contacting ethylene, an alpha-olefin, or acombination thereof, and a catalytic amount of a metal-ligand complexcatalyst of the formula (I):

where M is titanium, zirconium, or hafnium and has a formal oxidationstate of +2, +3, or +4; n is 0, 1, or 2; when n is 1, X is a monodentateligand or a bidentate ligand; when n is 2, each X is an independentlychosen monodentate ligand; the metal-ligand complex is overallcharge-neutral; each Z is independently chosen from —O—, —S—,—N(R^(N))—, or —P(R^(P))—; L is (C₁-C₄₀)hydrocarbylene or(C₁-C₄₀)heterohydrocarbylene, provided such has a portion that comprisesa 2- to 8-carbon atom linker backbone linking the Z moieties, each atomof such 2- to 8-atom linker being independently a carbon atom or aheteroatom, wherein each heteroatom independently is O, S, S(O), S(O)₂,Si(R^(C))₂, Ge(R^(C))₂, P(R^(P)), or N(R^(N)), wherein independentlyeach R^(C) is unsubstituted (C₁-C₁₈)hydrocarbyl or the two R^(C) aretaken together to form a (C₂-C₉)alkylene, each R^(P) is unsubstituted(C₁-C₁₈)hydrocarbyl; and each R^(N) is unsubstituted(C₁-C₁₈)hydrocarbyl, a hydrogen atom; one of R^(1a) and R^(1b) ishalogen, and the other is methyl or hydrogen; R^(2a), R^(3a), R^(4a),R^(2b), R^(3b), R^(4b), R^(6c), R^(7c), R^(8c), R^(6d), R^(7d), andR^(8d) independently is a hydrogen atom; (C₁-C₄₀) F₃CO—, R₃Si—, R₃Ge—,RO—, RS—, RS(O)—, RS(O)₂—, R₂P—, R₂N—, R₂C═N—, NC—, RC(O)O—, ROC(O)—,RC(O)N(R)—, or R₂NC(O)—, or two of the R^(S) are taken together to forman unsubstituted (C₁-C₁₈)alkylene, wherein each R^(S) independently isan unsubstituted (C₁-C₁₈)alkyl; R^(5c) and R^(5d) are independently a(C₆-C₄₀)aryl or (C₁-C₄₀)heteroaryl; and each of the aryl, heteroaryl,hydrocarbyl, hydrocarbylene, and heterohydrocarbylene groups isindependently unsubstituted or substituted with one or more substituentsR^(S); and each R^(S) is independently a halogen atom, polyfluorosubstitution, perfluoro substitution, unsubstituted (C₁-C₁₈)alkyl, F₃C—,FCH₂O—, F₂HCO—, under conditions such that an ethylene homopolymer, analpha-olefin homopolymer, or an ethylene/alpha-olefin copolymer isformed, such having a weight average molecular weight that is reduced byat least 20 percent when compared with an otherwise identical ethylenehomopolymer, alpha-olefin homopolymer or ethylene/alpha-olefin copolymerprepared under identical conditions with a catalyst that is otherwiseidentical but wherein neither R^(1a) nor R^(1b) is a halogen atom. 6.The process of claim 5 wherein R^(1a) or R^(1b) is a halogen atom chosenfrom fluorine, chlorine, or iodine.
 7. The process of claim 5 whereinthe alpha-olefin is selected from the group consisting of (A) linearalpha-olefins having from 3 to 12 carbons, (B) branched alpha-olefinshaving from 5 to 16 carbons, and both (A) and (B).
 8. The process ofclaim 5, wherein R^(2a), R^(2b), R^(3a), R^(3b), R^(4a), R^(4b) arehydrogen.
 9. The process of claim 5, wherein the metal-ligand complexcatalyst of the formula (I) is:


10. The process of claim 5, wherein the metal-ligand complex catalyst ofthe formula (I) is:


11. The process of claim 5, wherein the metal-ligand complex catalyst ofthe formula (I) is: